The last (Vashon) glaciation of the Puget Lowland
Inputs:
global sea level
ice advance and retreat
isostatic depression and rebound
initial topography (a fiction!)
Ice advance and retreat were rapid. Seattle was covered by ice for less than 2,000 years. At glacial maximum about 1 km (3,000 ft) of ice covered Seattle.
glacier
fresh water
salt water
Ralph A. Haugerud -USGS